base: fix CurrencyConstraint

It was using "Reference" instead of the dedicated term "Currency Code".

Attribute Unicity constraint message was not correctly including the
reference, the error message was always "Another currency with reference
None already exists".

bt5/erp5_base/PropertySheetTemplateItem/portal_property_sheets/CurrencyConstraint/reference_existence_constraint.xml

@@ -38,7 +38,7 @@
         </item>
         <item>
             <key> <string>message_no_such_property</string> </key>
-            <value> <string>Reference must be defined</string> </value>
+            <value> <string>Currency Code must be defined</string> </value>
         </item>
         <item>
             <key> <string>portal_type</string> </key>

bt5/erp5_base/PropertySheetTemplateItem/portal_property_sheets/CurrencyConstraint/reference_unicity_constraint.xml

@@ -18,6 +18,14 @@
               <persistent> <string encoding="base64">AAAAAAAAAAM=</string> </persistent>
             </value>
         </item>
+        <item>
+            <key> <string>constraint_property</string> </key>
+            <value>
+              <tuple>
+                <string>reference</string>
+              </tuple>
+            </value>
+        </item>
         <item>
             <key> <string>description</string> </key>
             <value>
@@ -26,7 +34,7 @@
         </item>
         <item>
             <key> <string>filter_parameter</string> </key>
-            <value> <string>python: {\'portal_type\': (\'Currency\', ), \'validation_state\': (\'validated\', ),\'reference\': object.getReference()}</string> </value>
+            <value> <string>python: {\'portal_type\': (\'Currency\', ), \'validation_state\': (\'validated\', ), \'reference\': object.getReference()}</string> </value>
         </item>
         <item>
             <key> <string>id</string> </key>
@@ -34,7 +42,7 @@
         </item>
         <item>
             <key> <string>message_invalid_attribute_unicity</string> </key>
-            <value> <string>Another currency with reference ${value} already exists</string> </value>
+            <value> <string>Another currency with Currency Code ${value} already exists</string> </value>
         </item>
         <item>
             <key> <string>portal_type</string> </key>

bt5/erp5_core_test/TestTemplateItem/portal_components/test.erp5.testERP5Base.py

@@ -1231,6 +1231,31 @@ class TestERP5Base(ERP5TypeTestCase):
         currency_module.CurrencyModule_getCurrencyItemList(),
         [('', ''), ('VA', 'currency_module/validated')])
 
+  def test_CurrencyConstraint(self):
+    self._addPropertySheet('Currency', 'CurrencyConstraint')
+    currency_module = self.portal.currency_module
+    existing_currency = currency_module.newContent(
+      portal_type='Currency',
+      reference='CODE',
+    )
+    existing_currency.validate()
+    self.tic()
+    def cleanup():
+      self.portal.currency_module.manage_delObjects([existing_currency.getId()])
+      self.tic()
+    self.addCleanup(cleanup)
+
+    currency = currency_module.newContent(
+      portal_type='Currency',
+    )
+    self.assertIn(
+      'Currency Code must be defined',
+      [str(m.getMessage()) for m in currency.checkConsistency()])
+    currency.setReference('CODE')
+    self.assertIn(
+      'Another currency with Currency Code CODE already exists',
+      [str(m.getMessage()) for m in currency.checkConsistency()])
+
   def getWorkflowHistory(self, document, workflow_id):
     return self.portal.portal_workflow.getInfoFor(ob=document, name='history',
         wf_id=workflow_id)